Bacteria use caffeine as a food source too

Chris Nova, 25th May 2011

There is more proof that all forms of life share certain characteristics with humans. This time it’s our preference for caffeine.

A doctoral student at the University of Iowa has discovered a new bacterium that uses caffeine for food. The bacterium utilizes newly discovered digestive enzymes to break down the caffeine, which allows it to live and grow.

"We have isolated a new caffeine-degrading bacterium, Pseudomonas putida CBB5, which breaks caffeine down into carbon dioxide and ammonia," says Ryan Summers, who presented his research yesterday at the 111th General Meeting of the American Society for Microbiology in New Orleans.

Caffeine is made of carbon, nitrogen, hydrogen and oxygen; all of these are needed for bacterial cell growth. Inside the caffeine molecule are three configurations, known as methyl groups, composed of 1 carbon and 3 hydrogen atoms. This bacterium is able to successfully remove these methyl groups (a process known as N-demethylization) and essentially live on caffeine.

Summers and his associates have identified the three enzymes that cause the N-demethylization and the genes that code for these enzymes. Additional testing showed that the mixtures formed during break down of caffeine are regular building blocks for drugs used to treat asthma, improve blood flow and stabilize heart arrhythmias.

Presently these medications are hard to manufacture chemically. Using CBB5 enzymes would lead to easier pharmaceutical production, therefore lowering their cost. An additional potential application is the decaffeination of coffee and tea as an alternative to harsh chemicals currently used.

"This work, for the first time, demonstrates the enzymes and genes utilized by bacteria to live on caffeine," says Summers.

We aren't the only ones who can live on caffeine. Now that's interesting.